Solid-state imaging device and electronic apparatus

ABSTRACT

A solid-state imaging device includes a semiconductor layer on which a plurality of pixels are arranged along a light-receiving surface being a main surface of the semiconductor layer, photoelectric conversion units provided for the respective pixels in the semiconductor layer, and a trench element isolation area formed by providing an insulating layer in a trench pattern formed on a light-receiving surface side of the semiconductor layer, the trench element isolation area being provided at a position displaced from a pixel boundary between the pixels.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.14/279,632, filed May 16, 2014, which claims the benefit of JapanesePatent Application JP 2013-109636, filed May 24, 2013, the entiredisclosures of which are hereby incorporated herein by reference.

BACKGROUND

The present disclosure relates to a solid-state imaging device and anelectronic apparatus, and particularly to a solid-state imaging deviceincluding a trench element separation area and an electronic apparatusincluding the solid-state imaging device.

A solid-state imaging device includes a plurality of pixels arrangedalong a light-receiving surface side of a semiconductor substrate. Therespective pixels include a photoelectric conversion unit provided inthe semiconductor substrate, and a color filter and an on-chip lensprovided on the upper side of the semiconductor substrate.

In the solid-state imaging device having such a configuration, if lightthat has obliquely entered a light-receiving surface leaks to aphotoelectric conversion unit of an adjacent pixel, the light leakagebecomes a factor to cause color mixture and color shading.

In this regard, a configuration in which trench element isolation areasthat separate the photoelectric conversion units of the pixels areformed in the semiconductor substrate on the light-receiving surfaceside, and a light-shielding film is provided in the respective trenchelement isolation areas to prevent light leakage from occurring betweenadjacent pixels, has been proposed. In such a configuration, the widthof an opening of the trench is narrowed at a shallow position on thelight-receiving surface side, and a light-shielding film is embeddedonly in the trench at the shallow position. Accordingly, it is possibleto form a light-shielding film without generating a void, and to blocklight between the pixels effectively (see, for example, Japanese PatentApplication Laid-open No. 2012-178457).

SUMMARY

Even in a solid-state imaging device having a configuration in which atrench element isolation area is provided in a semiconductor substrate,however, the collapse of color balance occurs that depends on awavelength of received light and an incidence angle of the receivedlight, which is a factor to cause coloring.

In this regard, it is desirable to provide a solid-state imaging devicehaving favorable color balance without coloring, and an electronicapparatus using the solid-state imaging device.

According to an embodiment of the present disclosure, there is provideda solid-state imaging device including a semiconductor layer on which aplurality of pixels are arranged along a light-receiving surface being amain surface of the semiconductor layer, photoelectric conversion unitsprovided for the respective pixels in the semiconductor layer, and atrench element isolation area formed by providing an insulating layer ina trench pattern formed on a light-receiving surface side of thesemiconductor layer, the trench element isolation area being provided ata position displaced from a pixel boundary between the pixels.

In the solid-state imaging device having such a configuration, a trenchelement isolation area is located at a position displaced from theboundary of the pixels. Therefore, by making the direction in which thetrench element isolation area is displaced a direction that depends on awavelength of received light in the respective pixels, the volume andposition of the photoelectric conversion unit on the light-receivingsurface side on which the trench element isolation area is provided canbe caused to depend on the wavelength of the received light.Accordingly, it is possible to improve the color balance between lightof a short-wavelength photoelectrically converted in an area on thelight-receiving surface in which the trench element isolation area isprovided, and light of a long-wavelength photoelectrically converted inan area that is deeper than the area.

As a result, according to the present disclosure, it is possible tocapture an image with favorable color balance without coloring, and toimprove the imaging properties.

These and other objects, features and advantages of the presentdisclosure will become more apparent in light of the following detaileddescription of best mode embodiments thereof, as illustrated in theaccompanying drawings.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a schematic configuration diagram showing an exemplarysolid-state imaging device to which an embodiment of the presentdisclosure is applied;

FIG. 2 is a plan view of a main portion of a solid-state imaging deviceaccording to a first embodiment of the present disclosure;

FIG. 3 is a cross-sectional view of a main portion of the solid-stateimaging device according to the first embodiment, which corresponds tothe cross-section taken along the line A-A of FIG. 2;

FIG. 4 is a graph showing relative output with respect to light ofcolors received in a photoelectric conversion unit;

FIG. 5 is a graph showing the amount of absorbing blue light withrespect to the depth from a light-receiving surface of a semiconductorlayer (Si);

FIGS. 6A-6C are each a manufacturing process diagram of the solid-stateimaging device according to the first embodiment

FIGS. 7A-7B are each a graph of normalized sensitivity with respect toan incidence angle;

FIGS. 8A-8C are each a graph of absolute sensitivity with respect to anincidence angle;

FIG. 9 is a cross-sectional view showing the configuration of a mainportion of a solid-state imaging device according to a second embodimentof the present disclosure;

FIG. 10 is a cross-sectional view showing the configuration of a mainportion of a solid-state imaging device according to a third embodimentof the present disclosure;

FIG. 11 is a cross-sectional view showing the configuration of a mainportion of a solid-state imaging device according to a fourth embodimentof the present disclosure;

FIG. 12 is a plan view of a main portion of a solid-state imaging deviceaccording to a fifth embodiment of the present disclosure;

FIG. 13 is a cross-sectional view of a main portion of the solid-stateimaging device according to the fifth embodiment, which corresponds tothe cross-section taken along the line A-A of FIG. 12;

FIGS. 14A-14B are each a graph showing the amount of color mixture toadjacent pixel with respect to an incidence angle; and

FIG. 15 is a configuration diagram of an electronic apparatus accordingto a sixth embodiment of the present disclosure, which includes asolid-state imaging element to which an embodiment of the presentdisclosure is applied.

DETAILED DESCRIPTION OF EMBODIMENTS

Hereinafter, embodiments of the present disclosure will be describedwith reference to the drawings in the following order.

-   1. Schematic Configuration Example of Solid-state Imaging Device    according to Embodiment-   2. First Embodiment (First Example in which Position of Trench    Element Isolation Area is Displaced to Side of Pixel of    Long-wavelength)-   3. Second Embodiment (Second Example in which Position of Trench    Element Isolation Area is Displaced to Side of Pixel of    Long-wavelength)-   4. Third Embodiment (Third Example in which Position of Trench    Element Isolation Area is Displaced to Side of Pixel of    Long-wavelength)-   5. Fourth Embodiment (Fourth Example in which Position of Trench    Element Isolation Area is Displaced to Side of Pixel of    Long-wavelength)-   6. Fifth Embodiment (Example in which Position of Trench Element    Isolation Area is Displaced to Side of Pixel of Short-wavelength)-   7. Sixth Embodiment (Electronic Apparatus Using Solid-state Imaging    Device)

1. Schematic Configuration Example of Solid-State Imaging DeviceAccording to Embodiment

FIG. 1 shows the schematic configuration of an MOS (Metal OxideSemiconductor)-type solid-state imaging device, as an exemplarysolid-state imaging device according to an embodiment of the presentdisclosure.

A solid-state imaging device 1 shown in FIG. 1 has a pixel area 4 inwhich a plurality of pixels 3 including photoelectric conversion areasare two-dimensionally arranged on a surface of a supporting substrate 2.To the respective pixels 3 arranged in the pixel area 4, a pixel circuitincluding a photoelectric conversion area, a floating diffusion, areading gate, a plurality of transistors (so-called MOS transistors),and a capacitive element is provided. It should be noted that theplurality of pixels 3 may share a part of the pixel circuit.

In the peripheral portion of the pixel area 4, peripheral circuits suchas a vertical drive circuit 5, column signal processing circuit 6, ahorizontal drive circuit 7, and a system control circuit 8 are provided.

The vertical drive circuit 5 includes a shift register, for example,selects a pixel drive line 9, supplies a pulse for driving the pixels 3to the selected pixel drive line 9, and drives the pixels 3 arranged inthe pixel area 4 row by row. Specifically, the vertical drive circuit 5selectively scans the pixels 3 arranged in the pixel area 4 row by rowin a vertical direction successively. Then, through vertical drive lines10 disposed vertically to the pixel drive lines 9, the vertical drivecircuit 5 supplies a pixel signal based on a signal charge generateddepending on the amount of received light in the respective pixels 3 tothe column signal processing circuit 6.

The column signal processing circuit 6 is arranged to correspond to, forexample, columns of the pixels 3, and perform signal processing such asremoving noise of a signal output from the pixels 3 in one row for eachpixel column. Specifically, the column signal processing circuit 6performs signal processing such as correlated double sampling (CDS) forremoving unique fixed pattern noise of a pixel, signal amplification,and analog/digital (AD) conversion.

The horizontal drive circuit 7 includes, for example, a shift register,selects a destination of the column signal processing circuit 6 bysequentially outputting a horizontal scanning pulse, and causes thecolumn signal processing circuit 6 to output a pixel signal.

The system control circuit 8 receives an input clock and data forinstructing an operation mode or the like, and outputs data such asinternal information of the solid-state imaging device 1. Specifically,the system control circuit 8 generates a clock signal or control signalthat is a reference of the behavior of the vertical drive circuit 5, thecolumn signal processing circuit 6, the horizontal drive circuit 7, andthe like, based on a vertical synchronous signal, a horizontalsynchronous signal, and a master clock. Then, the system control circuit8 inputs these signals to the vertical drive circuit 5, the columnsignal processing circuit 6, the horizontal drive circuit 7, and thelike.

The peripheral circuits 5 to 8 and a pixel circuit provided in the pixelarea 4 constitute a drive circuit that drives the respective pixels 3.It should be noted that the peripheral circuits 5 to 8 may be arrangedto be laminated on the pixel area 4.

2. First Embodiment (First Example in which Position of Trench ElementIsolation Area is Displaced to Side of Pixel of Long-Wavelength)

In a first embodiment of the present disclosure, a description will bemade in the order of the configuration a solid-state imaging device 1-1according to the first embodiment, a method of producing the solid-stateimaging device 1-1, and effects of the first embodiment.

(Configuration of Solid-State Imaging Device 1-1)

FIG. 2 is a plan view of a main portion of the solid-state imagingdevice 1-1 according to the first embodiment, and shows 12 pixels in thecase where a semiconductor layer 20 in the pixel area 4 is viewed from alight-receiving surface side in a plan view. FIG. 3 is a cross-sectionalview of a main portion of the solid-state imaging device 1-1 accordingto the first embodiment, which corresponds to the cross-section takenalong the line A-A of FIG. 2. Hereinafter, the configuration of thesolid-state imaging device 1-1 according to the first embodiment will bedescribed based on FIGS. 2 and 3.

The solid-state imaging device 1-1 according to the first embodimentincludes the semiconductor layer 20 bonded to a supporting substratewhose illustration is omitted here, and is a rear-surface irradiationtype imaging device in which a transistor or a wiring layer whoseillustration is omitted here is provided on a side opposite to alight-receiving surface S that is a main surface of the semiconductorlayer 20.

In the semiconductor layer 20, division areas 21 in which impurities arediffused are provided. In the respective pixels 3 divided by thedivision areas 21, a photoelectric conversion unit 23 is provided.Moreover, on the side of the light-receiving surface S of thesemiconductor layer 20, trench element isolation areas 25characteristically arranged in this embodiment are provided. Inaddition, on the light-receiving surface S of the semiconductor layer20, a protective insulating layer 31, an insulating layer 33, and alight-shielding film 35 are provided in the stated order, and colorfilters 39 and on-chip lenses 41 are laminated via a planarizationinsulating film 37.

Hereinafter, the configuration of the semiconductor layer 20, the trenchelement isolation areas 25 provided in the semiconductor layer 20, andthe layers laminated on the light-receiving surface S of thesemiconductor layer 20 will be described.

(Semiconductor Layer 20)

The semiconductor layer 20 includes n-type single crystal orpolycrystalline silicon, and is formed by making the thickness of asemiconductor substrate formed of n-type single crystal silicon thin,for example. A main surface side of the semiconductor layer 20 is thelight-receiving surface S, and the plurality of pixels 3 are arrangedalong the light-receiving surface S. The respective pixels 3 arearranged as a red pixel 3R that receives red light, a green pixel 3Gthat receives green light, or a blue pixel 3B that receives blue light.Here, as an example, the case where the pixels of the colors 3 aretwo-dimensionally arranged in a Bayer pattern is shown.

The pixels of the colors 3R, 3G, and 3B arranged in a Bayer pattern arearranged in the same shape with respect to the light-receiving surface Sregardless of the wavelength of received light. Assuming that theboundary between one pixel 3 and the other pixel 3 is a pixel boundary 3a, for example, the respective pixels 3 surrounded by the pixelboundaries 3 a in the light-receiving surface S have a substantiallysquare flat shape with a uniform size.

In such a semiconductor layer 20, the division areas 21 formed asdiffusion areas of p-type impurities are provided. The respectivedivision areas 21 extend from a surface opposite to the light-receivingsurface S to the light-receiving surface S along the pixel boundaries 3a in the semiconductor layer 20 with the respective pixel boundaries 3 abeing a center.

In addition, in the semiconductor layer 20, the n-type photoelectricconversion unit 23 is provided for the respective pixels 3. Therespective n-type photoelectric conversion units 23 include an n-typearea divided by the division area 21 and the trench element isolationarea 25 to be described later, in the semiconductor layer 20. Thephotoelectric conversion unit 23 and the p-type division area 21constitute a photodiode, and the photoelectric conversion unit 23 is astoring area of charges photoelectrically converted in the respectivepixels 3.

It should be noted that although various impurity areas such as asurface diffusion layer and a source/drain of a transistor that isarranged in a normal rear-surface irradiation type solid-state imagingdevice and a surface diffusion layer are provided in addition to thedivision areas 21 and the photoelectric conversion units 23 in thesemiconductor layer 20, illustration and description thereof will beomitted here.

(Trench Element Isolation Areas 25)

The respective trench element isolation areas 25 are formed by providingthe protective insulating layer 31 and the insulating layer 33 in agroove pattern 20 a provided on the side of the light-receiving surfaceS of semiconductor layer 20, and providing the light-shielding film 35via the protective insulating layer 31 and the insulating layer 33. Thetrench element isolation area 25 having such a configuration ischaracteristically provided at a position displaced from the center ofthe pixel boundary 3 a on the light-receiving surface S. The directionin which the trench element isolation area 25 is displaced from thepixel boundary 3 a depends on the wavelength of received light in twopixels 3 divided by the trench element isolation area 25.

In particular, in the first embodiment, the trench element isolationarea 25 is provided to be displaced in a direction of a pixel out of twopixels 3 arranged adjacent thereto, which receives light of a longerwavelength. Specifically, in the configuration in which the pixels ofthe colors 3R, 3G, and 3B are arranged in a Bayer pattern, the trenchelement isolation area 25 between the green pixel 3G and the blue pixel3B is provided at a position displaced toward the side of the greenpixel 3G. On the other hand, the trench element isolation area 25between the green pixel 3G and the red pixel 3R is provided at aposition displaced toward the side of the red pixel 3R.

It should be noted that “the trench element isolation areas 25 isprovided at a position displaced from the center of the pixel boundary 3a” represents that the center of the width direction of the trenchelement isolation area 25 when viewed from the side of thelight-receiving surface S, i.e., the center of the opening width of thegroove pattern 20 a is displaced from the pixel boundary 3 a. Therefore,the trench element isolation area 25 may be provided on the pixelboundary 3 a.

In such a configuration, the width of the trench element isolation areas25 when viewed from the side of the light-receiving surface S, i.e., theopening width of the groove pattern 20 a may be constant in thelight-receiving surface S.

Accordingly, in the semiconductor layer 20, in a depth area in which thetrench element isolation area 25 is provided, the width of thephotoelectric conversion unit 23 in the arrangement direction of thepixels of the colors 3R, 3G, and 3B is larger in one pixel that receiveslight of a longer wavelength. For example, in a direction in which thegreen pixel 3G and the blue pixel 3B are adjacent thereto, a width wG ofthe photoelectric conversion unit 23 in the green pixel 3G is smallerthan a width wB of the photoelectric conversion unit 23 in the bluepixel 3B in a depth area in which the trench element isolation area 25is provided. On the other hand, in a direction in which the green pixel3G and the red pixel 3R are adjacent thereto, the width wG of thephotoelectric conversion unit 23 in the green pixel 3G is larger than awidth wR of the photoelectric conversion unit 23 in the red pixel 3R ina depth area in which the trench element isolation areas 25 is provided.

Therefore, in an area in which the trench element isolation area 25 isprovided, i.e., an area in which light of a short-wavelength isphotoelectrically converted being a surface area close to thelight-receiving surface S, the volume of the photoelectric conversionunit 23 in the pixels of the colors 3R, 3G, and 3B is larger in onepixel that receives light of a shorter wavelength.

On the other hand, in the semiconductor layer 20, the width of thephotoelectric conversion unit 23 in the pixels of the colors 3R, 3G, and3B is substantially constant in the arrangement direction of the pixelsin a depth area in which the trench element isolation area 25 is notprovided, i.e., an area in which light of a long-wavelength isphotoelectrically converted being an area distant from thelight-receiving surface S. Therefore, the volume of the photoelectricconversion unit 23 in the pixels of the colors 3R, 3G, and 3B isuniform.

Moreover, a depth d of the trench element isolation area 25 from thelight-receiving surface S may be any depth as long as light of theshortest-wavelength of received light of wavelengths in the respectivepixels 3 can be fully absorbed. For example, FIG. 4 is a graph showingrelative output with respect to a wavelength of light that passesthrough a color filter of the respective colors to be described laterand is received in the respective photoelectric conversion unit. Asshown in the graph, the wavelength range in which 80% of light of eachwavelength received in the photoelectric conversion unit is converted inthe photoelectric conversion unit and is output is set as the wavelengthrange of light of the respective colors to be received. Accordingly, thewavelength range of blue light hB is defined. Then, as shown in FIG. 5,a depth D (here, D=2300 nm) from the light-receiving surface S in whichthe blue light hB in the defined wavelength range is almost fullyabsorbed is a maximum value, and the depth d of the trench elementisolation area is set within the range of the depth D.

For example, FIG. 5 shows the amount of absorbing the blue light hB inthe case where the semiconductor layer 20 includes single crystallinesilicon. In this case, at a depth of about 2300 nm from thelight-receiving surface S, the blue light hB can be almost fullyabsorbed. Therefore, the depth d of the trench element isolation area 25is set to not more than D being 2300 nm.

In the trench element isolation area 25 arranged as described above, theprotective insulating layer 31 and the insulating layer 33 provided onthe light-receiving surface S of the semiconductor layer 20 cover theinner wall of the groove pattern 20 a. Furthermore, above the center ofthe groove pattern 20 a, the light-shielding film 35 is embedded via theprotective insulating layer 31 and the insulating layer 33.

The protective insulating layer 31 includes a metal oxide that storesnegative charges, and forms a hole accumulation layer on the interfaceof the semiconductor layer 20. Such a protective insulating layer 31includes an oxide such as hafnium (Hf), aluminum (Al), tantalum (Ta),and titanium (Ti). On the other hand, the insulating layer 33 includessilicon oxide (SiO₂) or silicon nitride (SiN).

(Light-Shielding Film 35)

The light-shielding film 35 is pattern-formed above the light-receivingsurface S via the protective insulating layer 31 and the insulatinglayer 33. The light-shielding film 35 is embedded in the groove pattern20 a of the trench element isolation area 25 to form a part of thetrench element isolation area 25. In addition, above the light-receivingsurface S, the light-shielding film 35 is patterned to have an opening35 a above the photoelectric conversion unit 23. The opening 35 a mayhave the same shape in the pixels of the colors 3R, 3G, and 3B, and thecenter of the opening 35 a corresponds to a pixel center φ.

In addition, the light-shielding film 35 is pattern-formed above thelight-receiving surface S to have a line width with the pixel boundary 3a being a center. The line width may be constant, and the center of theline width may correspond to the pixel boundary 3 a. For example, thelight-shielding film 35 has a line width that covers the trench elementisolation area 25 when viewed from the side of the light-receivingsurface S in a plan view.

Such a light-shielding film 35 includes a metal material havinglight-shielding properties such as tungsten (W), aluminum (Al), titaniumnitride (TiN), and titanium (Ti).

In addition, the light-shielding film 35 patterned as described above iscovered by the planarization insulating film 37.

(Color Filter 39)

The color filters 39 are a layer provided on the planarizationinsulating film 37, and each include a color filter of each colorpatterned for the respective pixels 3. The patterned color filter 39 isconfigured to cause light within a wavelength range to be received inthe respective pixels 3R, 3G, and 3B to transmit therethrough. The colorfilters 39 may have the same shape in the pixels of the colors 3R, 3G,and 3B, and the center of the respective color filters 39 may correspondto the pixel center φ.

(On-Chip Lens 41)

The on-chip lenses 41 are arranged for the respective pixels 3 on thecolor filters 39, and each are a convex lens being convex with respectto an incidence direction of light, for example, here. Favorably, suchon-chip lenses 41 have the same shape in the pixels of the colors 3R,3G, and 3B, and the center of the respective on-chip lenses 41corresponds to the pixel center φ.

(Method of Producing Solid-State Imaging Device 1-1)

FIG. 6 are each a cross-sectional process diagram showing the procedureof producing the solid-state imaging device according to the firstembodiment. Hereinafter, with reference to FIG. 6, a method of producingthe solid-state imaging device according to the first embodiment shownin FIG. 2 and FIG. 3 will be described.

(FIG. 6A)

As shown in FIG. 6A-6C, in the semiconductor layer 20 including, forexample, n-type single crystalline silicon, the p-type division areas 21are formed by the diffusion of impurities from a surface opposite to thelight-receiving surface S first. The respective division areas 21 areformed to have a certain width with the boundary between the pixels 3two-dimensionally arranged equally on the light-receiving surface S ofthe semiconductor layer 20 (pixel boundary 3 a) being a center.

Moreover, although illustration is omitted here, an impurity diffusionlayer is formed in the semiconductor layer 20 as necessary, a wiringlayer is formed on a surface opposite to the light-receiving surface Sof the semiconductor layer 20, the wiring layer is covered by aninsulating film, and a supporting substrate is bonded thereto. Afterthat, the semiconductor layer 20 is polished from the side of thelight-receiving surface S to obtain a desired film thickness.

Next, on the side of the light-receiving surface S of the semiconductorlayer 20, the groove patterns 20 a are formed. The respective groovepatterns 20 a are formed to have the depth d that extends from thelight-receiving surface S to the division area 21 along the pixelboundary 3 a at a position displaced from the center of the pixelboundary 3 a in a width direction. The displacement of the groovepattern 20 a with respect to the pixel boundary 3 a and the depth d arethe same as those of the trench element isolation area described withreference to FIG. 3 previously. Such a groove pattern 20 a is formed byapplying a lithography technique to form a mask pattern on thelight-receiving surface S, and etching the semiconductor layer 20 withthe mask pattern.

Accordingly, the semiconductor layer 20 including n-type singlecrystalline silicon is divided by the p-type division areas 21 and thegroove pattern 20 a, and respective portions obtained by the divisionare the n-type photoelectric conversion unit 23. The width and thevolume in the arrangement direction of the pixels of the colors 3R, 3G,and 3B of the photoelectric conversion unit 23 in the respective pixels3 are larger in a pixel that receives light of a shorter wavelength in adepth area in which the groove pattern 20 a is provided, i.e., surfacearea close to the light-receiving surface S. On the other hand, in adepth area in which the groove pattern 20 a is not provided, i.e., areadistant from the light-receiving surface S, the width and the volume ofthe photoelectric conversion unit 23 in the pixels of the colors 3R, 3G,and 3B are uniform.

(FIG. 6B)

Next, as shown in FIG. 6B, the protective insulating layer 31 and theinsulating layer 33 are deposited in the stated order on thelight-receiving surface S of the semiconductor layer 20 so as to coverthe inner wall of the groove pattern 20 a. At this time, the protectiveinsulating layer 31 including a metal oxide is deposited with an atomiclayer deposition (ALD) method, for example. Next, the insulating layer33 including silicon oxide or silicon nitride is deposited with aplasma-enhanced chemical vapor deposition (CVD) method. Here, theprotective insulating layer 31 and the insulating layer 33 are formedwith a film thickness such that the groove pattern 20 a is not embedded.

After that, the insulating layer 33 and the light-shielding film 35 aredeposited with a sufficient film thickness such that the inside of thegroove pattern 20 a is embedded and light is blocked. At this time, thelight-shielding film 35 including a metal material is deposited with asputtering method, for example.

In this way, the trench element isolation areas 25 are obtained byembedding the protective insulating layer 31, the insulating layer 33,and the light-shielding film 35 in the groove pattern 20 a formed in thesemiconductor layer 20.

(FIG. 6C)

Next, as shown in FIG. 6C, the light-shielding film 35 is patterned onthe insulating layer 33, and the opening 35 a are formed above thephotoelectric conversion unit 23. At this time, the opening 35 a mayhave the same shape in the respective pixels of the colors 3R, 3G, and3B, and the center of the opening 35 a corresponds to the pixel centerφ. In addition, the light-shielding film 35 is patterned such that thecenter of the line width of the light-shielding film 35 corresponds tothe center of the pixel boundary 3 a in the state where the opening 35 ais formed and the trench element isolation areas 25 are covered by thelight-shielding film 35 when viewed from the side of the light-receivingsurface S in a plan view.

(FIG. 3)

After that, as shown in FIG. 3, the planarization insulating film 37 isformed above the insulating layer 33 so as to cover the patternedlight-shielding film 35. Next, the color filters of the colors 39 arepattern-formed for the pixels 3 on the planarization insulating film 37,and the on-chip lenses 41 are pattern-formed on the color filters 39. Asdescribed above, the color filters 39 and the on-chip lenses 41 may havethe same shape in the pixels of the colors 3R, 3G, and 3B, and thecenter of the respective color filters 39 and the respective on-chiplenses 41 correspond to the pixel center φ.

In this way, the solid-state imaging device 1-1 is produced.

Effects of First Embodiment

In the above-mentioned solid-state imaging device 1-1, the trenchelement isolation areas 25 formed on the side of the light-receivingsurface S of the semiconductor layer 20 are provided to be displaced ina direction that depends on the wavelength of light to be received.Accordingly, the solid-state imaging device 1-1 has a configuration inwhich a pixel that receives light of a shorter wavelength of in an areain which light of short-wavelength is photoelectrically converted has alarger area, and the volume of the colors 3R, 3G, and 3B is uniform inan area in which light of long-wavelength is photoelectricallyconverted.

Therefore, it is possible to prevent the sensitivity of receiving theblue light hB from reducing due to the decrease in the volume on theside of the light-receiving surface S by the trench element isolationareas 25, and to improve the sensitivity shading in the blue pixel 3B.Accordingly, as shown in FIG. 7A, it is possible to cause the normalizedsensitivities with respect to an incidence angle of light on thelight-receiving surface S to correspond to each other in red light hR,green light hG, and the blue light hB. As a result, the color balancethat depends on the sensitivity incidence angle is improved, and it ispossible to prevent coloring from occurring.

It should be noted that in the existing configuration in which thetrench element isolation areas 25 are arranged not to be displaced fromthe pixel boundary 3 a, the sensitivity shading of the blue light hB islarger than those of the red light hR and the green light hG, as shownin FIG. 7B. Therefore, the color balance that depends on the sensitivityincidence angle is collapsed and coloring occurs.

Moreover, in the configuration of the first embodiment, thelight-shielding film 35 is common between the pixels of the colors 3R,3G, and 3B, and the position of the light-shielding film 35 correspondsto the position of the pixel boundary 3 a. Therefore, vignetting ofincident light on the light-shielding film 35 is common between thepixels of the colors 3R, 3G, and 3B. Therefore, as shown in FIG. 8A, itis possible to equalize the sensitivity shading without decreasing theabsolute sensitivity at the incidence angle of 0°.

On the other hand, in the existing configuration in which the trenchelement isolation areas 25 are arranged not to be displaced from thepixel boundary 3 a, as shown in FIG. 8B, the sensitivity shading of theblue light hB is significantly large regardless of the absolutesensitivity as compared with those of the red light hR and the greenlight hG. Moreover, in the configuration in which the light-shieldingfilm 35 is displaced to the side of the pixel of a long-wavelength inorder to prevent the sensitivity shading of the blue light hB fromoccurring, although the color dependency of the sensitivity shading isimproved as shown in FIG. 8C, the absolute sensitivity is decreased inthe blue pixel 3B of a short-wavelength.

In the configuration of the first embodiment, however, because coloringcan be prevented from occurring by improving the color balance dependingon the sensitivity incidence angle without decreasing the absolutesensitivity, it is possible to improve the imaging characteristics.

Moreover, in the configuration of the first embodiment, thelight-shielding film 35 is arranged in the groove pattern 20 a of thetrench element isolation area 25. Therefore, light is prevented fromleaking from an adjacent pixel 3 via the insulating layer 33 between thelight-receiving surface S and the light-shielding film 35. Accordingly,it is also possible to prevent color mixture from occurring.

It should be noted that in the first embodiment, the configuration inwhich the pixels of the colors 3R, 3G, and 3B are arranged in a Bayerpattern has been described as an example. However, the solid-stateimaging device according to an embodiment of the present disclosure isnot limited to be applied to such a configuration. For example, in theconfiguration in which complementary colors of cyan and yellow are usedfor color filters, the trench element isolation area is provided to bedisplaced to the side of a pixel of cyan with respect to the pixelboundary 3 a between a pixel of cyan and a pixel of yellow. On the otherhand, in the configuration in which a pixel of white is used, the trenchelement isolation area is provided to be displaced to the side of apixel of white with respect to the pixel boundary 3 a between a pixel ofthe respective colors and the pixel of white. Accordingly, it ispossible to obtain the similar effects.

3. Second Embodiment (Second Example in which Position of Trench ElementIsolation Area is Displaced to Side of Pixel of Long-Wavelength)

(Configuration of Solid-State Imaging Device 1-2)

FIG. 9 is a cross-sectional view showing the configuration of a mainportion of a solid-state imaging device 1-2 according to a secondembodiment of the present disclosure. The solid-state imaging device 1-2according to the second embodiment shown in FIG. 9 is different from thesolid-state imaging device according to the first embodiment in that thelight-shielding film 35 is not embedded in a trench element isolationarea 45. Other configurations of the solid-state imaging device 1-2 arethe same as those of the first embodiment. Therefore, the same componentas that of the first embodiment is not described again.

Specifically, the trench element isolation area 45 has a configurationin which the insulating layer 33 is embedded via the protectiveinsulating layer 31 in the groove pattern 20 a formed on the side of thelight-receiving surface S of the semiconductor layer 20. The arrangementof the groove pattern 20 a with respect to the pixel boundary 3 a is thesame as that of the first embodiment. The configurations of theprotective insulating layer 31 and the insulating layer 33 are the sameas those of the first embodiment, and the second embodiment is differentfrom the first embodiment in that the protective insulating layer 31 andthe insulating layer 33 have film thicknesses that embed the groovepattern 20 a. In addition, the light-shielding film 35 is patterned onthe insulating layer 33 similarly to the first embodiment, but thesecond embodiment is different from that first embodiment in that thelight-shielding film 35 only has to have a film thickness that issufficient to block light.

(Method of Producing Solid-State Imaging Device 1-2)

In order to produce the solid-state imaging device 1-2 having such aconfiguration, the groove pattern 20 a may be fully embedded with theprotective insulating layer 31 and the insulating layer 33 when theprotective insulating layer 31 and the insulating layer 33 that havebeen described with reference to FIG. 6B are deposited in the productionof the solid-state imaging device according to the first embodiment.Other processes may be the same as those of the first embodiment.

Effects of Second Embodiment

Also in the solid-state imaging device 1-2 according to the secondembodiment having such a configuration, the trench element isolationareas 45, the light-shielding film 35, and the on-chip lenses 41 arearranged with respect to the pixels of the colors 3R, 3G, and 3Bsimilarly to the first embodiment. Therefore, because coloring can beprevented from occurring by improving the color balance depending on thesensitivity incidence angle without decreasing the absolute sensitivitysimilarly to the first embodiment, it is possible to improve the imagingcharacteristics.

4. Third Embodiment (Third Example in which Position of Trench ElementIsolation Area is Displaced to Side of Pixel of Long-Wavelength)

(Configuration of Solid-State Imaging Device 1-3)

FIG. 10 is a cross-sectional view showing the configuration of a mainportion of a solid-state imaging device 1-3 according to a thirdembodiment of the present disclosure. The solid-state imaging device 1-3according to the third embodiment shown in FIG. 10 is different from thesolid-state imaging device according to the first embodiment in that thepattern width of a trench element isolation area 47 is formed in astepwise manner in a depth direction. Other configurations of thesolid-state imaging device 1-3 are the same as those of the firstembodiment. Therefore, the same component as that of the firstembodiment is not described again.

Specifically, the trench element isolation area 47 has a two-steppattern width that is wide on the side of the light-receiving surface Sand is narrow at a deep position of the semiconductor layer 20. Such atrench element isolation area 47 is provided to be displaced from thepixel boundary 3 a at a wide portion of the pattern width on the side ofthe light-receiving surface S. On the other hand, at a narrow portion ofthe pattern width distant from the light-receiving surface S in thetrench element isolation area 47, the center of the pattern width maycorrespond to the pixel boundary 3 a.

The depth of such a trench element isolation area 47 at a wide portionof the pattern width is set to the depth d described in the firstembodiment previously.

In the trench element isolation area 47, the light-shielding film 35 maybe embedded only in the wide portion of the pattern width. Accordingly,the trench element isolation area 47 has a configuration in which thelight-shielding film 35 can be embedded without generating a void.

(Method of Producing Solid-State Imaging Device 1-3)

In order to produce the solid-state imaging device 1-3 having such aconfiguration, the groove pattern 20 a only has to be formed to have atwo-step opening width by an etching process using two masks two timeswhen the groove pattern 20 a that has been described with reference toFIG. 6A is formed in the production of the solid-state imaging deviceaccording to the first embodiment. Other processes may be the same asthose of the first embodiment.

Effects of Third Embodiment

Also in the solid-state imaging device 1-3 according to the thirdembodiment having such a configuration, the trench element isolationareas 47, the light-shielding film 35, and the on-chip lenses 41 arearranged with respect to the pixels of the colors 3R, 3G, and 3Bsimilarly to the first embodiment. Therefore, because coloring can beprevented from occurring by improving the color balance depending on thesensitivity incidence angle without decreasing the absolute sensitivitysimilarly to the first embodiment, it is possible to improve the imagingcharacteristics. Moreover, the trench element isolation area 47 has aconfiguration in which the light-shielding film 35 is arranged in thegroove pattern 20 a. Therefore, light is prevented from leaking fromadjacent pixels 3 similarly to the first embodiment. Accordingly, it isalso possible to prevent color mixture from occurring.

5. Fourth Embodiment (Fourth Example in which Position of Trench ElementIsolation Area is Displaced to Side of Pixel of Long-Wavelength)

(Configuration of Solid-State Imaging Device 1-4)

FIG. 11 is a cross-sectional view showing the configuration of a mainportion of a solid-state imaging device 1-4 according to a fourthembodiment of the present disclosure. The fourth embodiment shown inFIG. 11 is a modified example of the third embodiment. The solid-stateimaging device 1-4 is different from the solid-state imaging deviceaccording to the first embodiment in that the pattern width of a trenchelement isolation area 49 is formed in a stepwise manner in a depthdirection. Other configurations of the solid-state imaging device 1-4are the same as those of the first embodiment. Therefore, the samecomponent as that of the first embodiment is not described again.

Specifically, the trench element isolation area 49 has a two-steppattern width that is wide on the side of the light-receiving surface Sand is narrow at a deep position of the semiconductor layer 20. Such atrench element isolation area 49 is provided to be displaced from thepixel boundary 3 a at a wide portion and a narrow portion of the patternwidth on the side of the light-receiving surface S. That is, the groovepattern 20 a constituting the trench element isolation area 49 has ashape obtained by digging an opening portion with a narrow width fromthe bottom center of an opening portion with a wide width formed on theside of the light-receiving surface S.

The entire depth of such a trench element isolation area 49, whichincludes a wide portion and a narrow portion of the pattern width, isset to the depth d described in the first embodiment previously.

Moreover, in the trench element isolation area 49, the light-shieldingfilm 35 may be embedded only in a wide portion of the pattern width.Accordingly, the trench element isolation area 49 has a configuration inwhich the light-shielding film 35 can be embedded without generating avoid.

(Method of Manufacturing Solid-State Imaging Device 1-4)

In order to produce the solid-state imaging device 1-4 having such aconfiguration, a portion of the wide opening width of the groove pattern20 a on the side of the light-receiving surface S is formed by anetching process using a mask first when the groove pattern 20 a that hasbeen described with reference to FIG. 6A is formed in the production ofthe solid-state imaging device according to the first embodiment. Next,the groove pattern 20 a with a gradually narrowed opening width may beformed by forming side walls on side walls of the groove pattern 20 aand further applying an etching process to the bottom center of thegroove pattern 20 a. Other processes may be the same as those of thefirst embodiment.

Effects of Fourth Embodiment

Also in the solid-state imaging device 1-4 according to the fourthembodiment having such a configuration, the trench element isolationareas 49, the light-shielding film 35, and the on-chip lenses 41 arearranged with respect to the pixels of the colors 3R, 3G, and 3Bsimilarly to the first embodiment. Therefore, because coloring can beprevented from occurring by improving the color balance depending on thesensitivity incidence angle without decreasing the absolute sensitivitysimilarly to the first embodiment, it is possible to improve the imagingcharacteristics. Moreover, the trench element isolation area 49 has aconfiguration in which the light-shielding film 35 is arranged in thegroove pattern 20 a. Therefore, light is prevented from leaking fromadjacent pixels 3 similarly to the first embodiment. Accordingly, it isalso possible to prevent color mixture from occurring.

6. Fifth Embodiment (Example in which Position of Trench ElementIsolation Area is Displaced to Side of Pixel of Short-Wavelength)

(Configuration of Solid-State Imaging Device 1-5)

FIG. 12 is a plan view of a main portion of a solid-state imaging device1-5 according to a fifth embodiment of the present disclosure, and shows12 pixels in the case where a semiconductor layer portion of the pixelarea 4 is viewed from a light-receiving surface side in a plan view.FIG. 13 is a cross-sectional view of a main portion of the solid-stateimaging device 1-5 according to the fifth embodiment, which correspondsto the cross-section taken along the line A-A of FIG. 12. Hereinafter,the configuration of the solid-state imaging device 1-5 according to thefifth embodiment will be described based on FIGS. 12 and 13.

The solid-state imaging device 1-5 according to the fifth embodimentshown in FIGS. 12 and 13 is different from the solid-state imagingdevice according to the first embodiment in that a trench elementisolation area 51 is displaced from the pixel boundary 3 a in directionthat is different from that of the first embodiment and thelight-shielding film 35 is not embedded in the trench element isolationarea 51. Other configurations of the solid-state imaging device 1-5 arethe same as those of the first embodiment. Therefore, the same componentas that of the first embodiment is not described again.

Specifically, the trench element isolation area 51 has a configurationin which the protective insulating layer 31 and the insulating layer 33are embedded in the groove pattern 20 a. The trench element isolationarea 51 having such a configuration is provided at a position displacedfrom the center of the pixel boundary 3 a on the light-receiving surfaceS, and the displacement direction depends on the wavelength of light tobe received by two pixels 3 divided by the trench element isolation area51.

In particular, in the fifth embodiment, the trench element isolationarea 51 is provided to be displaced in a direction of one pixel of twopixels 3 arranged adjacent thereto, the one pixel receiving a light of ashorter wavelength. Specifically, in the case of the configuration inwhich the pixels of the colors 3R, 3G, and 3B are arranged in a Bayerpattern, the trench element isolation area 51 between the green pixel 3Gand the red pixel 3R is provided at a position displaced to the side ofthe green pixel 3G. On the other hand, the trench element isolation area51 between the green pixel 3G and the blue pixel 3B is provided at aposition displaced to the side of the blue pixel 3B.

Here, “the trench element isolation area 51 is provided at a positiondisplaced from the center of the pixel boundary 3 a” represents that thecenter of the width direction when the trench element isolation area 51is viewed from the side of the light-receiving surface S, i.e., thecenter of opening width of the groove pattern 20 a is displaced from thepixel boundary 3 a. Therefore, the trench element isolation area 51 maybe arranged on the pixel boundary 3 a.

In such a configuration, the width when the trench element isolationarea 51 is viewed from the side of the light-receiving surface S, i.e.,the opening width of the groove pattern 20 a may be constant in thelight-receiving surface S.

Accordingly, in the semiconductor layer 20, a pixel that receives lightof a short-wavelength is distant from the opening 35 a of thelight-shielding film 35 in an adjacent pixel, in a depth area in whichthe trench element isolation area 51 is provided, i.e., a surface areaclose to the light-receiving surface S. For example, in a direction inwhich the green pixel 3G and the red pixel 3R are adjacent thereto, thetrench element isolation area 51 is arranged to be displaced to the sideof the green pixel 3G. Accordingly, the light-receiving surface S of thegreen pixel 3G is arranged to be distant from the opening 35 a of thelight-shielding film 35 in the red pixel 3R.

On the other hand, in the semiconductor layer 20, the widths of thephotoelectric conversion unit 23 of the pixels of the colors 3R, 3G, and3B are almost the same in two arrangement directions and the volumes ofthe photoelectric conversion unit 23 of the pixels of the colors 3R, 3G,and 3B are uniform in a depth direction in which the trench elementisolation area 51 is not provided.

(Method of Producing Solid-State Imaging Device 1-5)

In order to produce the solid-state imaging device 1-5 having such aconfiguration, the position of the groove pattern 20 a to be formed isdisplaced to the side of a pixel that receives light of ashort-wavelength range when the groove pattern 20 a that has beendescribed with reference to FIG. 6A is formed in the production of thesolid-state imaging device according to the first embodiment. Moreover,the groove pattern 20 a may be fully embedded with the protectiveinsulating layer 31 and the insulating layer 33 when the protectiveinsulating layer 31 and the insulating layer 33 that have been describedwith reference to FIG. 6B are deposited. Other processes may be the sameas those of the first embodiment.

Effects of Fifth Embodiment

In the solid-state imaging device 1-5 according to the fifth embodimentdescribed above, the trench element isolation area 51 formed on the sideof the light-receiving surface S of the semiconductor layer 20 isprovided to be displaced in a direction that depends on a wavelength oflight to be received with respect to the pixel boundary 3 a.Accordingly, in an area on the side of the light-receiving surface S inwhich the trench element isolation area 51 is provided, a pixel thatreceives light of a short-wavelength is arranged to be distant from theopening 35 a of the light-shielding film 35 in an adjacent pixel, andthe volumes of the pixels of the colors 3R, 3G, and 3B are uniform in adeeper position.

Therefore, it is possible to prevent leakage of light from occurring bydiffraction of the red light hR due to making the photoelectricconversion unit 23 of an adjacent green pixel 3G distant from theopening 35 a of the light-shielding film 35 in the red pixel 3R, and thecolor mixture from generating thereby. Accordingly, as shown in FIG.14A, it is possible to cause the amounts of color mixture to an adjacentpixel with respect to an incidence angle in the red light hR, the greenlight hG, and the blue light hB to correspond to each other. As aresult, the color balance depending on the sensitivity incidence angleis improved, and it is possible to prevent coloring from occurring.

It should be noted that in the existing configuration in which thearrangement of the trench element isolation area is not displaced from apixel boundary, as shown in FIG. 14B, the amount of leakage to anadjacent pixel in the red light hR is larger than those of the bluelight hB and the green light hG. Therefore, the color balance dependingon the sensitivity incidence angle is collapsed, and coloring is easy tooccur.

In the configuration of the fifth embodiment, the light-shielding film35 is common between the pixels of the colors 3R, 3G, and 3B, and theposition of the light-shielding film 35 corresponds to the position ofthe pixel boundary 3 a. Therefore, vignetting of incident light on thelight-shielding film 35 is common between the pixels of the colors 3R,3G, and 3B, and the absolute sensitivity at the incidence angle of isnot decreased.

As a result, according to the solid-state imaging device of the fifthembodiment, because it is possible to prevent color mixture depending onthe incidence angle from occurring and to prevent coloring fromoccurring, the imaging characteristics cam be improved.

7. Sixth Embodiment (Electronic Apparatus Using Solid-State ImagingDevice)

The solid-state imaging device having the respective configurationsdescribed in the first embodiment to the fifth embodiment of the presentdisclosure can be provided to a camera system such as a digital cameraand a video camera, a mobile phone having an imaging function, or as asolid-state imaging device for an electronic apparatus such as anotherdevice having an imaging function.

FIG. 15 is a configuration diagram of a camera using a solid-stateimaging device, which serves as an exemplary electronic apparatusaccording to a six embodiment of the present disclosure. The cameraaccording to this embodiment is, for example, a video camera that iscapable of taking still images or videos. A camera 91 includes thesolid-state imaging device 1, an optical system 93 that guides incidentlight into a light receiving sensor unit in the solid-state imagingdevice 1, a shutter device 94, a drive circuit 95 that drives thesolid-state imaging device 1, and a signal processing circuit 96 thatprocesses an output signal of the solid-state imaging device 1.

The solid-state imaging device 1 is a solid-state imaging device havingthe configuration described in the first embodiment to the fifthembodiment. The optical system (optical lens) 93 causes image light(incident light) of an object to be formed on an imaging surface of thesolid-state imaging device 1. On the imaging surface, a plurality ofpixels are arranged, and incident light from the optical system 93 isguided to the photoelectric conversion areas of the solid-state imagingdevice, which constitute the pixels. Accordingly, in the photoelectricconversion areas of the solid-state imaging device 1, signal charges arestored in a certain period of time. Such an optical system 93 may be anoptical lens system including a plurality of optical lenses. The shutterdevice 94 controls the light irradiation period of time and lightblocking period of time to the solid-state imaging device 1. The drivecircuit 95 supplies a drive signal to the solid-state imaging device 1and the shutter device 94, and controls the signal output operation ofthe solid-state imaging device 1 to the signal processing circuit 96 andthe shutter operation of the shutter device 94 by the supplied drivesignal (timing signal). Specifically, the drive circuit 95 performs anoperation of signal transfer from the solid-state imaging device 1 tothe signal processing circuit 96 by supplying a drive signal (timingsignal). The signal processing circuit 96 performs various signalprocesses on the signal transferred from the solid-state imaging device1. The video signal subjected to a signal process is stored in a storingmedium such as a memory or is output to a monitor.

According to the electronic apparatus of this embodiment describedabove, because it includes the solid-state imaging device havingfavorable imaging properties described in the above-mentionedembodiments, it is possible to capture an image with high precision byan electronic apparatus having an imaging function.

It should be noted that the present disclosure may also take thefollowing configurations.

-   (1) A solid-state imaging device, including:

a semiconductor layer on which a plurality of pixels are arranged alonga light-receiving surface being a main surface of the semiconductorlayer;

photoelectric conversion units provided for the respective pixels in thesemiconductor layer; and

a trench element isolation area formed by providing an insulating layerin a trench pattern formed on a light-receiving surface side of thesemiconductor layer, the trench element isolation area being provided ata position displaced from a pixel boundary between the pixels.

-   (2) The solid-state imaging device according to (1), in which

the trench element isolation area is displaced from the pixel boundaryin a direction that depends on a wavelength of light to be received inthe respective pixel.

-   (3) The solid-state imaging device according to (1) or (2), further    including

a light-shielding film provided on an upper side of the light-receivingsurface of the semiconductor layer, the light-shielding film having anopening on an upper side of the photoelectric conversion units, thelight-shielding film being pattern-formed to have a line width with thepixel boundary being a center.

-   (4) The solid-state imaging device according to (3), in which

the trench element isolation area is covered by the light-shieldingfilm.

-   (5) The solid-state imaging device according to any one of (1) to    (4), further including

a color filter of each color provided on an upper side of thelight-receiving surface of the semiconductor layer, the color filterbeing pattern-formed so that a center of the color filter corresponds toa center of the pixel.

-   (6) The solid-state imaging device according to any one of (1) to    (5), further including

an on-chip lens provided on an upper side of the light-receiving surfaceof the semiconductor layer, the on-chip lens being pattern formed sothat a center of the on-chip lens corresponds to a center of the pixel.

-   (7) The solid-state imaging device according to any one of (1) to    (6), in which

the trench element isolation area is provided to be displaced in adirection of one pixel of the pixels arranged adjacent thereto, the onepixel receiving light of a longer wavelength.

-   (8) The solid-state imaging device according to (7), in which

in a center of the trench pattern of the trench element isolation area,a light-shielding film is embedded.

-   (9) The solid-state imaging device according to any one of (1) to    (8), in which

the trench element isolation area is formed to have a line width in astepwise manner, the line width being increased on a side of thelight-receiving surface.

-   (10) The solid-state imaging device according to (9), in which

at least a portion of the trench element isolation area on the side ofthe light-receiving surface is displaced from the pixel boundary.

-   (11) The solid-state imaging device according to any one of (1) to    (6), in which

the trench element isolation area is provided to be displaced in adirection of one pixel of the pixels arranged adjacent thereto, the onepixel receiving light of a shorter wavelength.

-   (12) The solid-state imaging device according to any one of (1) to    (11), in which

the semiconductor layer includes a division area including an impurityarea on the pixel boundary, the division area extending from a surfaceopposite to the light-receiving surface to the trench element isolationarea.

-   (13) An electronic apparatus, including:

a semiconductor layer on which a plurality of pixels are set along alight-receiving surface being a main surface of the semiconductor layer;

photoelectric conversion units provided for the respective pixels in thesemiconductor layer;

a trench element isolation area formed by providing an insulating layerin a trench pattern formed on a light-receiving surface side of thesemiconductor layer, the trench element isolation area being provided ata position displaced from a pixel boundary between the pixels; and

an optical system that guides incident light to the photoelectricconversion units.

It should be understood by those skilled in the art that variousmodifications, combinations, sub-combinations and alterations may occurdepending on design requirements and other factors insofar as they arewithin the scope of the appended claims or the equivalents thereof.

What is claimed is:
 1. An imaging device, comprising: a semiconductorsubstrate having a first side as a light incident side and a second sideopposite to the first side, the first side and the second side eachextending in a first direction; a plurality of photoelectric conversionunits disposed in the semiconductor substrate; a first trench regiondisposed in the semiconductor substrate between two of the plurality ofphotoelectric conversion units in the first direction; a first metalregion disposed adjacent to the first side such that the first metalregion is above at least a part of the first trench region in a seconddirection, the second direction being perpendicular to the firstdirection; a second trench region disposed in the semiconductorsubstrate adjacent to at least one of the plurality of photoelectricconversion units in the first direction; a second metal region disposedadjacent to the first side such that the second metal region is above atleast a part of the second trench region in the second direction; afirst opening of the first trench corresponding to a first color filter;and a second opening of the second trench corresponding to a secondcolor filter; wherein the first trench region and the second trenchregion are offset in opposite directions from a boundary between thefirst color filter and the second color filter and the first metalregion is offset from a center portion of the first trench region in anopposite direction than the second metal region is offset from a centerportion of the second trench region, wherein a size of the first openingand a size of the second opening are substantially the same, and whereina color of the first color filter is different from a color of thesecond color filter.
 2. The imaging device according to claim 1, whereinthe first metal region is offset from a pixel boundary of a pixel in adirection that depends on a wavelength of light to be received in thepixel.
 3. The imaging device according to claim 1, further comprising: alight-shielding film including the first metal region and the secondmetal region provided on a light-receiving side of the first side, thelight-shielding film having an opening and being pattern-formed to havea line width with a pixel boundary being a center of the light-shieldingfilm.
 4. The imaging device according to claim 1, further comprising: aninsulating layer included in the first trench region and the secondtrench region, wherein the insulating layer includes a metal oxide. 5.The imaging device according to claim 1, wherein color filters of eachcolor are provided on a light-receiving side of the first side, thecolor filters being pattern-formed so that a center of each one of thecolor filters corresponds to a center of each one of respective pixels.6. The imaging device according to claim 1, further comprising: anon-chip lens provided on a light-receiving side of the first side, theon-chip lens being pattern formed so that a center of the on-chip lenscorresponds to a center of a respective pixel.
 7. The imaging deviceaccording to claim 4, wherein a light-shielding film is embedded in acenter of the first trench region.
 8. The imaging device according toclaim 1, wherein the light-shielding film is a metal material comprisingat least one of tungsten, aluminum, titanium nitride, and titanium. 9.The imaging device according to claim 1, wherein the first trench regionis formed to have a line width in a stepwise manner, the line widthbeing increased on a side of the light incident side.
 10. The imagingdevice according to claim 9, wherein at least a portion of the firsttrench region on the side of the light incident side is displaced from apixel boundary.
 11. The imaging device according to claim 4, wherein theinsulating layer comprises one of silicon oxide or silicon nitride. 12.The imaging device according to claim 1, wherein the semiconductorsubstrate includes a division area including an impurity area on a pixelboundary, the division area extending from the second side to the firsttrench region.
 13. The imaging device according to claim 1, wherein thefirst trench region, a light-shielding film, and an on-chip lens arepositioned with respect to at least one of a plurality of pixels toarrange a desired sensitivity incidence angle such that the imagingdevice is devoid of coloring without decreasing an absolute sensitivity.14. The imaging device according to claim 13, wherein a vignetting ofincident light on the light-shielding film is common among at leastthree different color pixels from the plurality of pixels.
 15. Theimaging device according to claim 1, wherein color filters of each colorare provided on a light-incident side of the first side, the colorfilters being pattern-formed so that the centers of each of the colorfilters correspond to centers of respective pixels.
 16. The imagingdevice according to claim 1, further comprising: a set of pixels,wherein a first pixel in the set of pixels is closer to an edge of theset of pixels than a second pixel, wherein the first metal region isdisposed corresponding to the first pixel and the second metal region isdisposed corresponding to the second pixel, and wherein the first metalregion is offset from a pixel boundary of the first pixel in a greateramount than the second metal region is offset from a pixel boundary ofthe second pixel.
 17. The imaging device according to claim 16, furthercomprising: a set of microlens, wherein a first microlens is offset fromthe pixel boundary of the first pixel in a greater amount than thesecond microlens is offset from the pixel boundary of the second pixel.18. The imaging device according to claim 1, wherein the first metalregion is offset from a pixel boundary of a pixel in an offset directionand an amount that depends on a wavelength of light to be received inthe pixel.
 19. The imaging device according to claim 18, wherein theimaging device has a plurality of pixels that are arranged on the firstside of the semiconductor substrate, wherein an amount of the offsetdepends on a location within the plurality of pixels.
 20. The imagingdevice according to claim 18, wherein the imaging device has a pluralityof pixels that are arranged on the first side of the semiconductorsubstrate, wherein an amount of the offset is greater the further awaythat the first metal region is from a center of the plurality of pixels.21. The imaging device according to claim 1, wherein the first and thesecond metal regions do not include an embedded portion extending withinthe first and the second trench regions, and wherein the imaging devicehas an improved color balance without a decrease in an absolutesensitivity of the imaging device.
 22. The imaging device according toclaim 2, wherein a volume and a position of a photoelectric conversionunit of the respective pixel depends on the wavelength of the light. 23.The imaging device according to claim 22, wherein a color balancebetween light of a short wavelength photoelectrically converted in afirst area on the light incident side and light of a long wavelengthphotoelectrically converted in a second area that is deeper than thefirst area is improved.
 24. The imaging device according to claim 3,further comprising: a set of pixels having pixel boundaries includingthe pixel boundary, wherein a first pixel in the set of pixels is closerto an edge of the set of pixels than a second pixel, wherein the firstmetal region is disposed corresponding to the first pixel and the secondmetal region is disposed corresponding to the second pixel, and whereinthe first metal region is offset from a first pixel boundary of thefirst pixel in a greater amount than the second metal region is offsetfrom a second pixel boundary of the second pixel.
 25. The imaging deviceaccording to claim 24, further comprising: a set of microlens, wherein afirst microlens is offset from the first pixel boundary of the firstpixel in a greater amount than the second microlens is offset from thesecond pixel boundary of the second pixel.
 26. The imaging deviceaccording to claim 4, wherein the insulating layer is disposed at thefirst side of the semiconductor substrate.
 27. The imaging deviceaccording to claim 1, further comprising: a protective insulating layerincluded in the first trench region and the second trench region,wherein the protective insulating layer includes a metal oxide.
 28. Theimaging device according to claim 27, wherein the metal oxide is atleast one of hafnium, aluminum, and tantalum.
 29. The imaging deviceaccording to claim 27, wherein the protective insulating layer isdisposed at the first side of the semiconductor substrate.
 30. Anelectronic apparatus, comprising: an imaging device, comprising: asemiconductor substrate having a first side as a light incident side anda second side opposite to the first side, the first side and the secondside each extending in a first direction; a plurality of photoelectricconversion units disposed in the semiconductor substrate; a first trenchregion disposed in the semiconductor substrate between two of theplurality of photoelectric conversion units in the first direction; afirst metal region disposed adjacent to the first side such that thefirst metal region is above at least a part of the first trench regionin a second direction, the second direction being perpendicular to thefirst direction; a second trench region disposed in the semiconductorsubstrate adjacent to at least one of the plurality of photoelectricconversion units in the first direction; a second metal region disposedadjacent to the first side of the semiconductor substrate such that thesecond metal region is above at least a part of the second trench regionin the second direction; a first opening of the first trenchcorresponding to a first color filter; and a second opening of thesecond trench corresponding to a second color filter; wherein the firsttrench region and the second trench region are offset in oppositedirections from a boundary between the first color filter and the secondcolor filter and the first metal region is offset from a center portionof the first trench region in an opposite direction than the secondmetal region is offset from a center portion of the second trenchregion, wherein a size of the first opening and a size of the secondopening are substantially the same, and wherein a color of the firstcolor filter is different from a color of the second color filter.